Answer: 15/64 or approx. 23.4% odds
Steps:
Let us count the number of possibilities of getting 4 heads of 6 flips - we do not care about the order within the group of heads so this count is the number of combinations of 4 out of 6, or [tex]{6\choose{4}}=\frac{6! }{4!2!}=15[/tex]
The number of all possible outcomes of 6 coin flips is [tex]2^6[/tex].
So the probability is the ratio [tex]P=\frac{15}{64}\approx 0.234[/tex]
